ambienthutton

Hi guys, newbie here. I recently brought a second hand m13. This morning I went to set it up and I only get sound while the pedal is in bypass mode. If I engage an effect then I get silence. I tried on about 5 different guitars, 3 amps and a host of cables to rule out any other silly problems. My dignoses is that the fault is within the m13 unit. Has anyone else had this issue? Is it resolvable or have I brought a fluff? I was very excited to map out some sounds but alas I won’t be able too!